1. Field of the Invention
The present invention relates to a technique for controlling a light distribution pattern according to the position of a forward vehicle.
2. Description of the Related Art
As a conventional technique, an automotive headlamp apparatus has been proposed, which is configured to acquire an image of a forward area ahead of the user's vehicle, to calculate the distance or relative distance between it and the user's vehicle by performing image processing on the image thus acquired, and to switch the forward light distribution pattern based upon the calculation result. Typically, in order to provide enhanced distance visibility, a high beam light distribution pattern is used. Also, in order to reduce glare to a forward vehicle, a vehicle lighting device has been proposed which is configured to be capable of switching the light distribution pattern to a so-called light shielding high beam light distribution pattern obtained by shielding a part of the high beam light distribution pattern. A technique has been advanced for switching the light distribution pattern, in which the shape of a shading member is changed, and the optical axis is caused to rotate (swivel) rightward and leftward.
However, with an arrangement in which the distribution pattern is switched by changing the shape of a shading member, the area in which shielding can be provided is limited. Thus, depending on the position of a forward vehicle, there is room for providing a high level of compatibility between two improvements having a trade-off relation, i.e., enhanced forward visibility and reduction in glare to a forward vehicle.